[Valgrind-users] [OT] %ebx changing in poll()

[Nicholas N. <nj...@ca...>]

Hi,

This is slightly off-topic but since I discovered it when hacking Valgrind
it's worth a shot:  I find that when the poll() system call is made,
sometimes the value of %ebx (which holds the 1st argument) changes, being
increased by 8.  A sample call:

  poll ( 0x804A6C0, 0, 0 )

(which returns 0) doesn't change %ebx.  But another call:

  poll ( 0xBFFFF310, 1, 0 )

does.

No other syscall I've seen changes any of its argument (and I've checked
it on some pretty big programs).  I have a patched 2.4.19-3 kernel.

Any ideas?

N